This report summarized 6 factors which appear extremely important in determining the results of cardiac valve replacement in a particular patient. These factors include, 1) the type of substitute valve inserted; 2) the size of the substitute valve inserted; 3) the experience and technical skill of the surgeon; 4) the adequacy of the pump team, anesthesiologists and surgeons, physicians and nurses providing postoperative care; 5) the presence of associated (diagnosed or unadiagnosed) or uncorrected cardiac disease or previous pericardiotomy, and 6) the preoperative status of the patient.